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R: Data Analysis and Visualization by Ágnes Vidovics-Dancs, Kata Váradi, Tamás Vadász, Ágnes Tuza, Balázs Árpád Szucs, Julia Molnár, Péter Medvegyev, Balázs Márkus, István Margitai, Péter Juhász, Dániel Havran, Gergely Gabler, Barbara Dömötör, Gergely Daróczi, Ádám Banai, Milán Badics, Ferenc Illés, Edina Berlinger, Bater Makhabel, Hrishi V. Mittal, Jaynal Abedin, Brett Lantz, Tony Fischetti

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The sampling distribution

So, we have estimated that the true population mean is about 65.2; we know the population mean isn't exactly 65.19704—but by just how much might our estimate be off?

To answer this question, let's take repeated samples from the population again. This time, we're going to take samples of size 40 from the population 10,000 times and plot a frequency distribution of the means.

  > means.of.our.samples <- numeric(10000)
  > for(i in 1:10000){
  +   a.sample <- sample(all.us.women, 40)
  +   means.of.our.samples[i] <- mean(a.sample)
  + }
The sampling distribution

Figure 5.3: The sampling distribution of sample means

This frequency distribution is called a sampling distribution ...

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